Skin

A cross-section through animal skin is shown in Figure 3 3. The central fibrous dermis or corium layer is composed of long fine fibrils of the protein collagen, grouped together in units of between twenty and fifty to form fibres. The fibres are then further associated in bundles held together by reticular tissue. Fibre bundles interweave in a three-dimensional network that in all skins is larger and coarser towards the central thickness and finer and more compact in the layer close to the surface. Each animal type also shows characteristic variations in the pattern of the weave that markedly determine the properties of the leather made from it. The fibre structure also varies in different regions of the skin and in all skins there is a predominating direction in which the fibres run - aligned with the hair and the underlying muscle - that confers oriented properties of strength and elasticity on the skin and on leather prepared from it.

Rawhide is dried, untanned skin, usually a split cattle hide (see below) that, unlike tanned leather, will putrefy in warm moist environments. Its tendency to shrink on drying has been exploited to make drum seats.

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